Percussion mechanism and rotary drilling apparatus



Aug. 21, 1962 P. P. CAREY 3,050,033

PERCUSSION MECHANISM AND ROTARY DRILLING APPARATUS Filed Oct. 6, 1959 3 Sheets-Sheet 1 & I j ls g lo INVENTOR I DkUL P. CAIZET ATTORNEY- Aug. 21, 1962 P. P. CAREY 3,050,033

PERCUSSION MECHANISM AND ROTARY DRILLING APPARATUS Filed Oct. 6, 1959 5 Sheets-Sheet 2 I IN VENTOR 2I6 PAUL i CNZET BY 6 4M AQMZ? 6W 2l4 ATTORNEYS P. P. CAREY Aug. 21, 1962 3 Sheets-Sheet 3 Filed 001;. 6, 1959 PAUL D CNAET R 8 O O 0 O 8 I %n. a a m E V m 8 g m U 4 MP 2 2 w 2 m w m a m 2 8 64 2 2 o 6 5 6 6 8 8 9 2 2 2 J 1 4 WM 7 L K 2 4/ O 8 W 5 2 4 2 2 2 2 a y 2 a a"! T 2 w 2 2 1 2 3 2 1 2 M & 4 M Q 2 2O 2 2 2 O :2 22% 1/ 2/ a i w 2 2 2 2% w 2 6 o 4 O 4 F Z 2 2 22 w 2 ATTORNEYS United States Patent f 3,050,033 PERCUSSION MECHANISM AND ROTARY DRILLING APPARATUS Paul P. Carey, R0. Box 63, Houston, Tex. Filed Oct. 6, 1959, Ser. No. 844,751 7 Claims. (Cl. 121-28) This application relates to drilling and more particularly to an improved percussion hammer mechanism for use in the apparatus and method disclosed in co-pending application Serial No. 840,068 filed September 14, 1959.

In the above-mentioned co-pending application there is disclosed a method of drilling earth formation which utilizes apparatus of the type conventionally employed in rotary drilling. The novelty of the above-mentioned application resides in the realization that the drilling operation can be greatly improved by superimposing upon the conventional rotary drilling forces a series of downward percussion blows.

An object of the present invention is to provide a percussion hammer mechanism for performing the function noted above, such mechanism being fluid operated, preferably by fluid utilized to clean the cuttings from the formation being drilled.

Another object of the present invention is the provision of a percussion hammer mechanism of the type described having improved means for effecting a series of rapid percussion blows for transmittal to a rotary drilling bit on the lower end of a rotary drilling string, such means being operable by fluid energy, preferably the energy of the fluid utilized in the drilling installation to clean the cuttings from the formation being drilled.

Still another object of the present invention is the provision of a percussion hammer mechanism of the type described which is simple in construction and operation and which is economical to manufacture and maintain.

I These and other objects of the present invention will become more apparent during the course of the following detailed description and appended claims.

The invention may best be understood with reference to the accompanying drawings wherein an illustrative embodiment is shown.

In the drawings:

FIGURE 1 is a fragmentary cross-sectional view of an oil well installation showing one manner in which a percussion hammer mechanism embodying the principles of the present invention is employed therein;

FIGURE 2 is a view similar to FIGURE 1 showing another manner in which the percussion hammer mechanism of the present invention is employed therein;

FIGURE 3 is a vertical sectional view of the percussion hammer mechanism of the present invention showing the parts in the position they assume just after the percussion blow stroke;

FIGURE 4 is a view similar to FIGURE 3 showing the pants in the position they assume just prior to the percussion blow stroke;

FIGURE 5 is a fragmentary cross-sectional view taken along line 5-5 of FIGURE 3;

FIGURE 6 is a fragmentary cross-sectional view taken along the line -66 of FIGURE 3;

FIGURE 7 is a fragmentary cross-sectional view taken along the line '7-7 of FIGURE 3; and

FIGURE 8 is a fragmentary cross-sectional view taken along the line 88 of FIGURE 3.

Referring now more particularly to the drawings, there is.shown in FIGURES 1 and 2 a drilling installation of the type disclosed in co-pending application Serial No. 840,068, filed Sept. 14, 1959, illustrating two possible ways in which a percussion hammer mechanism embodying the principles of the present invention and generally 3,5ll,033 Patented Aug. 21, 1 962 ice indicated at 18, could be employed therein. As shown in FIGURES 1 and 2 the drilling installation includes a rotary type drilling bit, designated generally by reference character 10, connected to a device usually termed a rotary table, designated generally by reference character 12, for imparting rotary motion to the drag bit for drilling hole 14 in the formation. intervening between the bit 10 and the rotary table 12 is a length of conventional structure, usually in hollow or tubular form, sometimes referred to in the trade as drill string or drill rod. In FIGURE 1, this structure is designated by reference character 16 In FIGURE 2, the equivalent member appears in twosections designated 16A and 16B One manner in which the percussion hammer mechanism 18 of the present invention may be employed in a drilling installation of the type disclosed in the abovementioned co-pending application is shown in FIGURE 1, wherein the percussion hammer mechanism .18 is used above the surface 20 of the formation The rotary table 12 may be above or below the hammer mechanism 18, being shown below the hammer mechanism in FIGURE 1. A different manner of employing the percussion hammer mechanism 18 of the present invention is shown in FIGURE 2. In this case, the hammer mechanism 18 is used down in the hole intermediate the bit 10* and the formation surface 20. The dimension L shown in FIG- URE 2 is used for the purpose of explaining that the distance from the bit to the percussion hammer mechanism 18 may be different from one installation to another. The hammer mechanism may be located immediately on the bit 10 or a considerable distance up the drill string. The latter case of course merges with the case shown in FIGURE 1 where the hammer mechanism is above the surface of the formation. In any of :these cases the compressional waves generated by the percussion hammer mechanism are transmitted through the medium of the drill string to the cutting edges of the rotary bit 10. In the operation of the installation shown in FIGURES 1 and 2, the rotary table is actuated in any of the usual ways so that continuing rotation is imparted to the rotary drag bit 10.

The bit 19 will be caused to exert a downward force on the bottom of the hole being drilled in the formation due to the natural weight of the bit 161 and the drill string attached to and bearing down on the bit. As is well-known practice, particularly where the hole is shallow, if the natural weight of the bit, the drill string and associated parts is not heavy enough to exert suflicient rotary drilling force, a downward force may be created upon the rotary table so as to add to the force of the bit against the formation. One well-known way of increasing the drilling force is to have the rotary table mounted for example as on a truck, with provision for jacking the truck up on the rotary table so as to add the Weight of the truck to the forces of the bit against the formation.

However, there are cases where the hole becomes so deep that natural weight of the bit and drill string creates forces of the bit against the formation in excess of those which can be tolerated. In this type of situation, it is known to actually exert an upward force on the upper end of the drill string to take some of the load off of the bit. This is a situation intended to be applicable to the FIGURE 2 arrangement, where upward forces may actually be exerted through the medium of the swivel component 22. In any case where an upward force is being exerted on the upper end of the drill string to relieve the stress upon the bit, there Will be a certain point in the string between the bit and the swivel whereat, moving downwardly along the string, the internal stresses in the string changed from tensile stresses to compressional stresses. This can be calculated in advance from knowlthe distance L as defined above, when upward forces are.

applied to the upper end of the drill string. It appears that the percussion blows are transmitted to the bit with least attenuation when these waves need not travel through the part of the drill string under tension.

To complete the explanation of FIGURES 1 and 2, it may be added that usual rotary bit drilling calls for passage of flushing fluid downwardly through the interior of the drill string. Upon reaching the bit, ports are provided for this flushing fluid to emerge in the vicinity of the cutting edges, and the fluid then passes upwardly in the hole, carrying with it the cuttings, to a suitable cap structure 24 at the surface of the formation, which has a fluid outlet means 26 for exhausting the fluid with cuttings. 'Flushing fluid may be entered into the drill string by a suitable hose or like means 28 associated with the swivel structure 22.

Referring now more particularly to FIGURES 3-8, the percussion hammer mechanism for the present invention comprises a central, vertically extending core member, generally indicated at 210. The lower end portion of the time member has a central bore 214 formed in the lower end of the bore 212 for receiving a portion of the drill string 16 which extends downwardly fromthe mechanism. Formed in the core member 210 adjacent the threaded counterbore 214 is an annular flange 216, the

7 upper surface of which is arranged to. engage and receive the lower end of an outer casing or tubular member, generally indicated at 218; Formed on the. lower end of the casing 218 is a bottom wall 220, the lower surface of which is arranged to engage the upper surface of the flange 216. Of course, the bottom wall 220 is centrally apertured, as at 222, to receive the core member 212.

Mounted within the open upper end, of the. casing or tubular member 2It8 is an annular cap member 224 having the lower portion of its periphery relieved, as at 226, tov receive the upper end of the tubular member 218. The core member 210 includes an upper end portion 228 which extends upwardly through an opening 230 formed in the cap member 224 and suitable sealing means, such as annular seal 232, is preferably provided between the opening 230 and the upper end portion of the core memher 228.

The upper extremity of the core member end portion 228 is exteriorly threaded, to receive the lower end of the drill string 16 disposed above the percussion hammer mechanism 18. A spacer ring or washer 234 is mounted between the lower extremity of the drill string 16 and the upper surface of the cap member224 and serves to maintain the casing 218 and the cap member 224 in engagement with the flange 216 of the central core member 210. r

Mounted within the casing 218 is an anvil member generally indicated at 236. The anvil member includes a bottom wall 238 which is centrally apertured, as at 240, to receive the core member 210. Preferably suitable sealing means, such as annular seal 242, is provided between the opening 240 and the adjacent portion of the core member. The bottom wall 238 of the anvil member 236 is arranged to engage the bottom wall 220 of the casing and has a tubular wall 244 extending upwardly therefrom for threaded engagement with the lower Iecessed extremity of the cap member 224, as indicated at 246. A sleeve-like hammer member 248 mounted in surrounding relation to the core member 210 within the cylindrical wall 236 of the anvil member is arranged to reciprocate longitudinally within the chamber defined 4 a by the cylindrical wall 244, the lower end of the cap member 224 and the bottom wall 238.

As indicated above, the percussion hammer mechanism 18 of the present invention is arranged to be actuated by fluid, preferably the fluid utilized in the drilling installation to clean the cuttings from the bottom of the formation. To this end, the upper end portion 288 of the core member has formed therein a bore 250 which terminates inwardly of the core member in spaced relation to the inward termination of the lower bore 212. Fluid, as for example air, passing downwardly through the upper drill string 16, enters the bore 250' and passes radially outwardly therefrom selectively through a series of longitudinally spaced pairs of diametrically opposed, radially extending ports or openings'252, 254 and 256.

The flow of fluid through the ports 254 and 7256 is controlled by means of a valve member, generally indicated at 258. The valve member includes an upper hollow cylindrical portion 260 which closely embraces the upper end portion 228 of the core member for longitudinal sliding movement thereon. Formed in the cap member 224 is a first counter-bore 262 :for slidably receiving the upper end portion 260 ofthe valve member 258. The lower portion of the valve member 258 is formed into a generally bell-shaped configuration, as indicated at 264, and is arranged to slidably reciprocate within a second counterbore 266 formed in the cap member.

The flow of fluid through the lower ports 256 is controlled by means of an annular shoulder or valve seat 268 formed on the core member 210 adjacent the lower end of the reduced upper end portion 228 thereof, and a cooperating annular surface 270 formed on the bellshaped lower end portion 264 of the valve member.

The flow of fluid through the intermediate ports 254 is controlled by means of a pair of diametrically opposed ports 272 extending radially through the upper end portion 269 of, the valve member. The inner ends of the ports 272 communicate with an annular groove 274 formed in the interior surface of the upper end portion 260 of the valve member and the outer ends communicate with an annular groove 276 formed in the exterior surface of the end portion 260.

The annular groove 276 also controls the flow of fluid to upper and lower longitudinally spaced radially extending ports 278 and 280 formed in the adjacent portion of the cap member. As best shown in FIGURE 5, the inner end of the lower port 280 is arranged to communicate with the annular groove 276 and the outer end thereof communicates with the upper end of a longitudinally extending recess 282 formed in the exterior of the cylindrical wall 244 of the anvil member. Thelower extremity of the recess communicates with the interior of the cylindrical wall 244 adjacent the bottom wall 238 by means of a radially extending port 284. As best shown in FIGURES 3 and 4, the lower extremity of the hammer member 248 has its outer periphery relieved, as indicated at 286, to permit fluid from the port 284 to act upwardly on the hammer memben.

. As best shown in FIGURE 6, the outer end of the upper port 278 communicates radially with the upper end of a passage 288 extending longitudinally through the main cylindrical wall of the tubular casing 218. The lower end of the passage 288 communicates with the outer end of a passage 290 extending radially through the bottom wall 238 of the anvil member 236. As best shown in FIGURE 7, the inner end of the passage 290 communicates with an annular groove 292 formed in the opening 240 of the bottom wall 238. The annular groove 292 registers with an annular groove 294 formed in the exterior of the core member 210 and a pair of diametrically opposed ports 296 extending radially inwardly from the annular groove 294 into communication with the bore 212 formed in the core member 210.

The passage of fluid from the chamber within which the hammer member 248 is slidably mounted for longitudinal reciprocation is provided by pairs of diametrically opposed radially extending openings 298, 300 and 302 formed in the core member in communication with the bore 212.

Formed in the exterior periphery of the cylindrical wall 244 of the anvil member 236 in diametrically opposed relation to the passage 283 is a longitudinally extending valve actuating recess 304, the lower end of which communicates with the interior of the cylindrical wall 244 adjacent the bottom wall 238 by a radially extending passage 306. As best shown in FIGURE 8, the upper end of the recess 304 communicates with the upper end of the second counterbore 266 in the cap member 2224 by means of a radially extending passage 308 formed in the latter.

In operation, it will be understood that the hammer member 248 is longitudinally reciprocated within the chamber provided by the cylindrical wall 244 in a continuous cycle. For purposes of convenient description the operation of the percussion hammer mechanism will be set forth below beginning with that point in the cycle just after the hammer mechanism has delivered a per cussion blow.

As shown in FEGURE 3, in this position the hammer mechanism 248 will be disposed in the lower portion of the chamber in engagement with the bottom wall 238 of the anvil member. In addition, the valve member 258 be disposed in its lowermost position with the annular surface 270 in engagement with the valve seat 268 to prevent flow of fluid through the ports 256 and with the ports 272 of the valve member communicating the intermediate ports 254 with the port 280 and closing off flow to the port 278.

It will be seen that fluid from the upper portion of the drill string 16 enters the bore 250 will pass through the ports 254, valve ports 272, cap member port 280, recess 282 and port 284- intothe lower end of the hammer chamber, thus causing the hammer member therein to be moved upwardly. During the upward movement of the hammer member 248 the air in the hammer chamber thereabove will be forced outwardly through the openings 298 and 300. As the hammer member moves upwardly, the upper opening 298 will be covered so that during subsequent upward movement the air trapped in the upper portion of the chamber will act upon the lower bell-shaped end 264 of the valve member and move the same upwardly into the position shown in FIGURE 4. This movement of the valve member 258 interrupts communication between the valve port 272 and the inlet ports 256 of the core member 2-10 and communicates the. lower port 280 with the upper port 278 through the exterior annular groove 276 of the valve member. In addition, the annular surface 270 of the valve member moves away from the valve seat 26-8 permitting the lower ports 256 to communicate with the upper end of the hammer chamber. This condition of the hammer mechanism is illustrated in FIG- URE 4. It will be noted that the fluid from the drill string passing through the upper bore 250 will now pass through the lower ports 256 into the upper end of the hammer chamber, thus causing the hammer member 248 to move downwardly.

Downward movement of the hammer member 248 will cause the air in the lower portion of the hammer chamber to pass outwardly into the bore 212 through the lower openings 302. As the hammer member 248 closes the openings 302 during its downward movement, the air in the lower portion of the hammer chamber will be compressed and forced outwardly through port 284, recess 282, port 280, and then into port 278 through the exterior valve member recess 276. From the port 278 the air passes through the passage 288, port 290 and core member ports 296 into the bore 212. It will also be noted that during the downward movement of the hammer member 248 past the openings 302, the air in the lower portion of the hammer chamber will be compressed and this increase in pressure will also be transmitted through port 306, recess 304, port 308 and counterbore 266 which will cause the valve member to move downwardly into its lowermost position as shown in FIGURE 3.

Of course, at the end of the downward movement of the hammer member, the same will strike the bottom wall 238 of the anvil member with a percussion blow and the compression wave thus caused 'will be transmitted directly by the drill string connected to the lower end of the core member to the rotary drilling bit 10 on the lower end thereof. It will also be understood that the air or other fluid entering the bore 250 at the upper end of the hammer mechanism will eventually pass into the lower bore 212 from which it is directed by the pipe string 16 connected to the lower end of the hammer mechanism to the bottom of the formation being drilled through the rotary drill bit to perform the usual function of clearing the cuttings from the formation.

It will be noted that the fluid pressure entering the bore 250 will at all times pass into the upper end of the counterbore 262 through ports 2'52 and therefore act on the upper end of the valve member 258. The existance of this constant pressure acting downwardly on the valve member 258 aids in eifecting a movement of the valve member at the proper time in the cycle of operation, that is, prevents the creation of compression or vacuum conditions within the bore 262 which would detrirnentally effect the free movement of the valve member.

It thus will be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing specific embodiment has been shown and described only for the purpose of illustrating the principles of this invention and is subject to extensive change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.

I claim:

1. In apparatus for drilling earth formations, the combination comprising a rigid structure for fixed securement between lengths of drill string, said rigid structure including a central core member and means surrounding said core member defining an annular hammer chamber therearound, a hammer member mounted on said core member within said chamber for free longitudinal reciprocation therein, said rigid structure also having fluid passage means for directing a source of pressurized fluid into and out of opposite ends of said chamber, and valve means movably carried by said rigid structure spaced apart from said hammer member and operably disposed in relation to said fluid passage means for controlling the flow of fluid alternatively into opposite ends of said chamher to effect reciprocation of said hammer mechanismtherein, said valve mechanism being operably movable by the flow of fluid through said passage means in response to the reciprocating movement of said hammer member, said fluid passage means including a central bore formed in the upper end of said core member and spaced inlet ports communicating therewith for control by said valve mechanism.

2. The combination as defined in claim 1 wherein said rigid structure includes a head member adjacent the upper end of said hammer chamber, said head member including a central bore receiving the upper end of said core member and first and second counterbores formed in the lower portion of said bore, said valve member including an upper sleeve-shaped portion slidably mounted within said first counterbore and a lower bell-shaped portion slidably mounted in said second counterbore, said bell shaped portion being arranged to have fluid pressure act on the upper and lower surfaces thereof to effect the movement of said valve member in response to the movement of said hammer member.

3. In apparatus for drilling earth formations, the combination comprising an elongated core member having 7 means on opposite ends thereof for conne'cti'on'with lengths of drill string, casing means fixed to said core member defining annular hammer chamber thereabout, a'hammer member mounted on said core member within said chamber for longitudinal reciprocation therein, said core member having spaced upper and lower bores therein and spaced ports communicating each of said bores with the exterior of said core member, the ports communicating with said lower bore also communicating with said hammer chamber and flow therethrough being controlled by the reciprocating movement of said hammer member, separate passage means in said casing means for communicating the said upper bore ports with opposite ends of said hammber chamber, a valve member slidably mounted on said core member adjacent the ports therein communicating with said upperbore for movement between two positions, said valve member in one position permitting flow of fluid from said upper bore through one of the ports communicating therewith and into the one of said passage means communicating with one end of said hammer chamber and in the other position permittingfiflow of fluid from said upperbore through another of the ports communicating therewith and into the other of said passage means communicating with the opposite end of said hammer chamber to thereby effect reciprocation of said hammer, said valve member being movable between said positions by the movement of fluid through said passage meansand communicating ports in response to the reciprocating movement of said hammer member.

4. The combination as defined in claim 3 wherein said chamber defining means includes a head member adjacent the upper end of said chamber, said head member having a central bore therein receiving the upper end portion of said core member and first and second counterbores formed in the lower end of said central bore, said valve member including an upper sleeve-shaped portion slidably received within said first counterbore and a lower bellshaped portion siidably received in said second counterbore, the lower surface of said bell-shaped portion communioating with the upper end ofsaid chamber'so the fluid pressure therein resulting from the upward movement of said hammer member will effect upward movement of said valve member, said chamber defining meansproviding fluid passage means extending between the lower end of said hammer chamber and the upper end of said second counterbo-re for transmitting fluid pressure in the lower end of said chamber during downward movement of said hammer member to the upper surface of said bellshaped portion to efiect downward movement of said valve member.

5. The combination as defined in claim 4 wherein said core member also has formed therein a port communicating with said upper bore and the upper end of said first lcountenbore. V

6. In an apparatus for drilling earth formations, the combination comprising an elongated core member having means on opposite ends thereof for connection with lengths of drill string, said core member having an an 8 nular'fiange extending outwardly from the lower end thereof, means defining a hammer chamber around said core member including a tubular casing surrounding said core member and having a bottom wall engaging said annular flange, ahead member secured to the upper end of said casing and having a central. bore receiving the upper end portion'of said core member and first and second counterbores formed in the lower end of said bore, a valve member slidably mounted on said core member and having an upper sleeve-shaped portion movable in said first counterbore and a lower bell-shaped portion movable in said second counterbore, said core member having a central fluid inlet bore formed in'the upper end portion thereof and inlet port means extending therefrom, means including said valve member for alternately directing a source of fluid from said inlet port means to the upper and lower ends of said chamber respectively, said core member having a central fluid exhaust bore formed in the lower end portion thereof and upper and lower exhaust ports communicating with said bore and said hammer chamber in spaced relation to the upper and lower ends thereof respectively, a hammer member mounted onsaid core member within said chamber for reciprocating movement therein in response to the passage of fluid into op posite ends of said chamber, the lower end of said second 'counterbore communicating with the upper end of said hammer chamber above said upper exhaust port and passage means .in said casing communicating the upper end of said second counterbore with the lower end of said hammer chamber below said lower exhaust port whereby upward movement of said hammer member will exhaust fluid through said upper exhaust port, close the same, and then direct pressure fluid into the lower end of said second counterbore against the underside of said valve member to effect movement of said valve member upwardly and downward movement of said hammer member will we haust fluid through said lower exhaust port, close the same and than direct pressure fluid through said passage means into said upper end of said second counterbore to effect movement of said valve member downwardly.

7. The combination as defined in claim 6 wherein said chamber defining means also includes an inner anvil memher having a bottom wall engaging the bottom wall of said casing and a cylindrical peripheral wall engaging the tubular casing above the bottom wall thereof.

References Cited in the file of this patent UNITED STATES PATENTS 

